A diagnostic schema for alcoholism is described. Based upon the National Council on Alcoholism criteria for alcoholism diagnosis, this schema permits the classification of any client into one of five mutually exclusive diagnostic categories. The schema is applied to data from an independent study. A significant client‐type by treatment‐type interaction is reported as evidence of the schema's clinical utility. The discussion outlines the need for further diagnostic refinements within the criteria and suggests possible uses of the schema as a research t